The largely unregulated world of online knife sales was thrown into the spotlight yesterday when prosecutors said that either Robert Tulloch, 17, or James Parker, 16, bought a military-style knife on the Internet – and allegedly used it in the slaying of two Dartmouth College professors.

Will someone tell me what they think is so complicated about a knife that would prevent someone from just making one? It doesn’t take much to figure out how to put a sharp edge on a piece of metal or even a piece of plastic.